Hawai`i newborn hypothyroid cases linked to Fukushima radiation

There has been a lot of Hawai`i concern about radioactivity of marine debris from Japan’s March 2011 Fukushima nuclear plant meltdown, but the first actual physical impacts of the disaster have likely come from the sky.

The short version: Radiation in Hawai`i and the western states increased dramatically following  Fukushima, and shortly afterward, children born in these states displayed a statistically significant increase--16 percent-- in the rate of hypothyroidism, a disease that is associated with radiation.

Very soon after the radiation release, the radioactive particles were on their way across the Pacific on the winds, and very soon after that, newborns in Hawai`i and the western Mainland states began displaying possibly radiation-related thyroid disease.

A just-published, peer reviewed study shows that cases of hypothyroidism increased immediately following the Fukushima radiation release—in association with a dramatic increase in radioactivity levels.  

“There were increased concentrations of all beta-emitting radionuclides in the air during the six weeks following the beginning of Fukushima fallout. Compared to the same period a year earlier, the fallout increases were more than seven times greater in the five Pacific/West Coast States, compared to just over two times in the remainder of the US,” the paper says.

Of particular interest in this study was the isotope Iodine 131. Iodine is naturally drawn to the thyroid gland, and so is radioactive iodine. I-131 was virtually unknown in humans until the 1950s nuclear tests, at which time it was first isolated from adult thyroid glands. But the situation is far more serious for babies in utero.

“For decades radioactiveiodine has been recognized to cause adverse effects (including hypothyroidism) to the thyroid gland. The fetal thyroid, the first glandular structure to appear in the human embryo, begins to concentrate iodine and produce thyroid hormones by the 70th day of gestation,” wrote the authors of the paper, “Elevated airborne beta levels in Pacific/West Coast US States and trends in hypothyroidism among newborns after the Fukushima nuclear meltdown.”

The authors are Joseph J. Mangano and Janette D. Sherman of the Radiation and Public Health Project in New York. As they describe it, infants get the radioactive iodine from dairy products, and the cows get it “due to radioactive fallout deposition on forage.”

The Fukushima crisis created a pulse of radiation over the western U.S: “The largest amounts of radioactive fallout in the US environment from Fukushima occurred in late March and all of April 2011, before declining to levels typically recorded in 2010.”

The authors considered a number of other possible factors, including random variance in congential hypothyroidism numbers, but ultimately rejected them. “The statistical significance of the findings  make random yearly fluctuation unlikely as an explanation for the observed differences,” they wrote.

The authors are cautious with their data, and make the point that it’s early in the study of these connections: “The data presented in this paper, including both exposure levels and CH incidence, should be considered as preliminary. They require confirmation and expansion, including long-term follow-up of infants and other children. However, the current findings should be noted, and encourage the conduct of future analyses of health effects from exposures to Fukushima fallout.”

That said, their preliminary data seems compelling:

“Just days after the meltdowns, I-131 concentrations in US precipitation was measured up to 211 times above normal. Highest levels of I-131 and airborne gross beta were documented in the five US States on the Pacific Ocean. The number of congenital hypothyroid cases in these five states from March 17-December 31, 2011 was 16% greater than for the same period in 2010, compared to a 3% decline in 36 other US States. The greatest divergence in these two groups (+28%) occurred in the period March 17-June 30.”

While the American numbers are alarming, they are not nearly as serious as the impacts on Japanese children living near Fukushima, there, large proportions of children have displayed growths on their thyroid glands.  Here is one report on that phenomenon.

© Jan TenBruggencate 2013

This is the paper: J. Mangano, J. and D. Sherman, J. (2013) Elevated airborne beta levels in Pacific/West Coast US States and trends in hypothyroidism among newborns after the Fukushima nuclear meltdown. Open Journal of Pediatrics, 3, 1-9. doi: 10.4236/ojped.2013.31001.